Reading properties from Spring Cloud Config Server
本指南解释了你的 Quarkus 应用程序如何从 @ [14] 中在运行时读取配置属性。
This guide explains how your Quarkus application can read configuration properties at runtime from the Spring Cloud Config Server.
Prerequisites
Unresolved directive in spring-cloud-config-client.adoc - include::{includes}/prerequisites.adoc[]
Solution
我们建议你按照下一节中的说明逐步创建应用程序。
We recommend that you follow the instructions in the next sections and create the application step by step.
Stand up a Config Server
要建立本指南所需的 Config Server，请遵循 @ [18] 中概述的说明。该过程的最终结果是一个正在运行的 Config Server，它将在应用程序查询服务器被命名为 @ [17] 时为名为 @ [16] 的配置属性提供 @ [15] 值。
To stand up the Config Server required for this guide, please follow the instructions outlined here.
The end result of that process is a running Config Server that will provide the Hello world value for a configuration property named message when the application querying the server is named a-bootiful-client.
Creating the Maven project
首先，我们需要一个新项目。使用以下命令创建一个新项目：
First, we need a new project. Create a new project with the following command:
Unresolved directive in spring-cloud-config-client.adoc - include::{includes}/devtools/create-app.adoc[]
此命令生成一个导入 @ [19] 扩展名的项目。
This command generates a project which imports the spring-cloud-config-client extension.
如果你已配置了 Quarkus 项目，则可以通过在项目基础目录中运行以下命令向项目添加 @ [20] 扩展名：
If you already have your Quarkus project configured, you can add the spring-cloud-config-client extension
to your project by running the following command in your project base directory:
Unresolved directive in spring-cloud-config-client.adoc - include::{includes}/devtools/extension-add.adoc[]
这会将以下内容添加到构建文件中：
This will add the following to your build file:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-spring-cloud-config-client</artifactId>
</dependency>implementation("io.quarkus:quarkus-spring-cloud-config-client")GreetingController
首先，在 @ [22] 文件中创建一个简单的 @ [21] Jakarta REST 资源，如下所示：
First, create a simple GreetingResource Jakarta REST resource in the
src/main/java/org/acme/spring/cloud/config/client/GreetingResource.java file that looks like:
package org.acme.spring.spring.cloud.config.client;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
@Path("/hello")
public class GreetingResource {
@GET
@Produces(MediaType.TEXT_PLAIN)
public String hello() {
return "hello";
}
}由于我们想要使用从 Config Server 获取的配置属性，因此我们将更新 @ [23] 以注入 @ [24] 属性。更新后的代码看起来像这样：
As we want to use configuration properties obtained from the Config Server, we will update the GreetingResource to inject the message property. The updated code will look like this:
package org.acme.spring.spring.cloud.config.client;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
import org.eclipse.microprofile.config.inject.ConfigProperty;
@Path("/hello")
public class GreetingResource {
@ConfigProperty(name = "message", defaultValue="hello default")
String message;
@GET
@Produces(MediaType.TEXT_PLAIN)
public String hello() {
return message;
}
}Configuring the application
在 quarkus.spring-cloud-config 根下，Quarkus 提供了各种配置旋钮。为了本指南的目的，我们的 Quarkus 应用程序将配置在 application.properties 如下所示：
Quarkus provides various configuration knobs under the quarkus.spring-cloud-config root. For the purposes of this guide, our Quarkus application is going to be configured in application.properties as follows:
# use the same name as the application name that was configured when standing up the Config Server
quarkus.application.name=a-bootiful-client
# enable retrieval of configuration from the Config Server - this is off by default
quarkus.spring-cloud-config.enabled=true
# configure the URL where the Config Server listens to HTTP requests - this could have been left out since http://localhost:8888 is the default
quarkus.spring-cloud-config.url=http://localhost:8888|
如果您使用的是 Gradle，则 Gradle 设置 If you are using Gradle, the Gradle setting |
Package and run the application
使用以下内容运行应用程序：
Run the application with:
Unresolved directive in spring-cloud-config-client.adoc - include::{includes}/devtools/dev.adoc[]
用浏览器打开 [role="bare"][role="bare"]http://localhost:8080/greeting.
Open your browser to [role="bare"]http://localhost:8080/greeting.
结果应为 Hello world，因为它是从 Spring Cloud Config 服务器获取的值。
The result should be: Hello world as it is the value obtained from the Spring Cloud Config server.
Run the application as a native executable
您当然可以使用 Building a native executable guide 的说明创建一个本机映像。
You can of course create a native image using the instructions of the Building a native executable guide.